This invention relates to a braking system for a trailer vehicle.
The requirements for controlling the brakes of vehicles, particularly of heavy duty commercial vehicles, have become increasingly complex in recent times. One such requirement is that of providing an anti-lock braking system (ABS), in which locking or incipient locking of one or more braked wheels is detected and the braking level controlled to avoid such locking. Hitherto the control mechanism for heavy duty vehicle braking systems has usually been based on pneumatic control logic, when the medium which powers the brakes is air under pressure, but increasingly complex requirements for braking control lead to the adoption of an electronically controlled braking system (EBS).
When the vehicle is a trailer or semi-trailer, both herein referred to for convenience as a trailer, it may be drawn by a tractor which has an electronically controlled braking system or one which has a pneumatically controlled braking system. Although it would be desirable to provide a trailer with an electronically controlled braking system, if it is thus provided the system must be compatible for use with a tractor not having an electronically controlled braking system.
It is the object of the present invention to provide an electronically controlled braking system for a vehicle, particularly, but not exclusively, for a trailer, which meets the above requirement for compatibility.